For all those questions, the answer __in my case__ lead me to build my own system.

There's a dozen reliable ION mini-ITX motherboards so pick the one that fits your need (dual Atom ? onboard Wifi ? onboard Blue-tooth ? coax numerical audio out ? ). Some Zotacs even have an included power supply.

The hardest part for me was finding the exactly right computer case. I needed to reuse 2 normal hard drives (not 2.5in hdd like in laptops), a normal 5.25in optical drive, a passive PSU, and a WAF compliant design. I went for the Gigabyte MIB T5140, but only because it became available in stores before the Thermaltake Element Q, which was also a good choice for my needs.